The Sustainable Development Goals (SDGs) are important issues that should be learned about in school, particularly those related to sustainable cities and communities. Target 6 of the 11th Goal mentions the special attention that should be paid to air quality. Nature-based solutions are a current theme that should be learned in school to empower students to contribute to planetary sustainability. In this context, a pedagogical intervention was developed through problem-based learning addressing air pollution. After two lessons of 50 min each, students presented a worksheet answered in groups, a group snapshot reflection, and the results of filling out a digital mural before and after the intervention. After a content analysis, the results of this evaluation study were reflected in the 105 students’ increasing knowledge about nature-based solutions to improve air quality. A positive appreciation of problem-based learning as an active methodology that motivates and increases students’ participation was also referred to.